I don’t quite know why it should be that we expect great artists, or even mediocre ones, to be magnificent human beings.

Being intelligent, original and good at drawing/typing/ inventing tunes are not qualities that automatically guarantee moral rectitude, saintliness or even decency. (Or a particularly trenchant take on current affairs, something that television producers might bear in mind before inviting racist bigots who happen to be novelists onto their programmes to discuss, say, Iraq.)

You could argue – wrongly, I think, if you believe that great art concerns itself with humaneness – that someone who chooses to exist outside the confines of morality, unshackled and free, is more likely to produce truly bold and original art than some sweet, cautious, family-minded type.

Such a person may not be terribly nice – they may indeed be remarkably horrid – but likeability isn’t too much of a worry since we are uniquely forgiving of artists, provided they continue to produce dazzling work. Pre-Barack Obama, the last great hope for democracy in the West might have been brought crashing down by sperm and cigars, but artists – well, they’re artists, aren’t they? All sort of bohemian and unpredictable, so never mind if their private behaviour is beyond the pale.

This is quite odd, given that so many of them live – or behave – like pigs. V S Naipaul, the great novelist and Nobel laureate, is the subject of an authorised biography by Patrick French to be published next week. In it he concedes that his behaviour towards Patricia, his wife of 41 years – he kept a mistress for 24 years and then abandoned her for another woman – may have contributed to, or at least hastened, her death.

According to French, Patricia Naipaul knew about the mistress but learnt of her husband’s regular visits to prostitutes only after he boasted about them (rather nerdily) in a magazine interview in 1994. His wife had just had a mastectomy and was in remission from cancer at the time. “I think that consumed her,” Naipaul says in the biography. “I think she had all the relapses and everything after that. She suffered. It could be said that I killed her. It could be said. I feel a little bit that way.”

Speaking to French about admitting the existence of his mistress, Margaret Gooding, to his wife, Naipaul said: “I was liberated. She was destroyed. It was inevitable.” Naipaul finally ended the affair as his wife lay dying (“I feel that in all of this Margaret was very badly treated. But you know, there is nothing I can do”) and married somebody else two months after she was cremated. French has had access to her diaries. One entry reads: “Vidia told me he had not enjoyed making love to me since 1967.”

Literary circles are populated by adequate talents staggering comically under the weight of outsize egos. There are perhaps two dozen novelists writing today whose work will still be read in 50 years’ time, but that doesn’t stop the rest from being delusional. I was making small talk with a crime writer the other day and politely forced myself to ask him a question. “That’s one for the biographers,” he said, perfectly seriously (and note “biographers”, plural).

Even in these circles, though, Naipaul’s ego is in a class of its own. It’s all about him – “I was liberated”, “there is nothing I can do” – and his devotion to himself, his self possibly masquerading as his art. The artist’s refrain is always, “It’s all about my work”, which is a disingenuous way of saying, “It’s all about me.”

Still, Naipaul doesn’t reserve his appalling behaviour for his Wags: he is renowned for his literary fallings-out, notably with former friend Paul Theroux, and his recently published memoirs, the not at all hilariously titled A Writer’s People, savages Anthony Powell, the one established writer who championed Naipaul when he first came to England.

What is interesting rather than merely depressing about all of this is why the women stay. Literature is littered with miserable writers’ wives and a few of their corpses: see Vivienne Eliot, Zelda Fitzgerald, Sylvia Plath, all of whom had mental health issues that their husbands may or may not have tried their hardest to alleviate.

And there’s no shortage of literary unions where the wife’s own talents were subsumed to the husband’s (alleged) greatness, until divorce came along to rectify the balance: see Martha Gellhorn, who was married to Ernest Hemingway, or Elizabeth Jane Howard, who was married to Kingsley Amis.

Equally there are plenty of happy literary marriages, but they tend to fall into three distinct categories: 1) where the husband and wife write very different genres (as with a number of contemporary literary unions); 2) where the wife is the muse and facilitator or considers domestic achievements to be her work, along with her secretarial skills (as in Sonia Tolstoy, who wrote out War and Peace seven times); and 3) where there is an open marriage with affairs on both sides (as in – well, as in lots of people, but let’s try to avoid the libel suit).

Patricia Naipaul must have aimed for the second option, which is the trickiest one to pull off if one is to hold on to any sense of self. She clearly loved her husband deeply, became a sort of glorified cook and carer, helped along for a while by a dependency on Mandrax sedatives, and stayed with him until her death.

The level of casual cruelty she was subjected to may be extreme – you can almost picture Naipaul telling her some terrible, hurtful thing and then observing her reaction and taking notes – but what is telling is not only that she stayed, poor woman, but that he didn’t leave.

What this tells us is that artists – even self-obsessed, ultra-narcissistic ones such as Naipaul – may choose to live in an unorthodox way, but are at heart profoundly conservative. There isn’t a man alive who doesn’t simply want to be loved, admired, fed and slept with. That’s all they ask for: anything else such as holding an opinion or voicing a criticism is not only superfluous but actively undesirable.

Flattery, veneration, nice dinners and sex on tap are what make a happy union as far as men are concerned and the lack of even one of those components is what makes for affairs. That’s as true of artists as it is of accountants – truer, actually. It makes them very like the rest of humanity. But it’s worth looking elsewhere for moral guidance. As Anaïs Nin wrote of her relationship with Henry Miller: “At the core of us is a writer, not a human being.”

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